In order to distribute a .Net application, it would be wise to make an install file to bundle up all the dependency files your program needs into one package that can be easily installed onto the users computer. Also, as with all .Net programs, the user will need the .Net framework installed to run.

There are several ways to make install/setup files, I think the easiest might be the way that Microsoft included ever-so-generously in Visual Studio .Net.
You can add a new Setup Project to your solution (File > Add Project > New Project > Setup and development > ...)
and then from this you can play around with the settings and figure it out, it isnt that hard to pick up. You need to add your projects primary output and all the dependency files.